1. Field of the Invention
The present invention relates to a method of testing a semiconductor chip and, more specifically, to a method of testing electrical characteristics of a semiconductor chip such as a passivated IC chip.
2. Description of the Related Art
In a conventional method of testing electrical characteristics of an IC chip, the characteristics are detected using a test IC chip or a test wafer which is assembled without a passivation treatment. On the contrary, the electrical characteristics of a passivated IC chip or wafer are conventionally tested by removing a passivation film formed thereon by plasma etching or the like.
When an assembled IC is defective, usually, its IC chip is tested by entirely removing a passivation film of the IC chip and then bringing a probe of a manual prober into contact with a micro pattern, thereby to find a defect.
There does not occur any problem in testing an IC chip on which no passivation film is formed. However, when an IC chip on which a passivation film is formed is tested, all the passivation film other than the part to be tested needs to be removed, thus increasing the number of testing steps. Since a wiring layer or aluminum pattern 2 formed on IC chip 1 is tested by putting minute probe 3 having a small capacitance into contact with aluminum pattern 2 as shown in FIG. 1, probe 3 slips out of aluminum pattern 2 and therefore a stable inspection cannot be performed. Furthermore, the electrical characteristics of an IC itself are varied by entirely removing the passivation film.